1. Field of the Invention
Example embodiments of the present invention relate to a method of forming a layer and a method of removing reaction by-products. More particularly, example embodiments of the present invention relate to a method of forming a layer and a method of removing reaction by-products to reduce and/or prevent a lifting phenomenon from occurring, which may be caused by the reaction by-products.
2. Description of the Related Art
Recently, semiconductor devices have become smaller and increasingly highly integrated. Accordingly, design rules of the semiconductor devices have become relatively strict. Thus, a diffusion of metal in a metal layer may have a great influence on the semiconductor devices. A metal/metal nitride layer such as a titanium/titanium nitride layer, for example, may be used as a barrier layer to reduce and/or prevent the diffusion of the metals.
In conventional arts, a process for forming a titanium layer and a process for forming a titanium nitride layer are performed in different chambers. That is, the titanium layer may be formed by a plasma enhanced chemical vapor deposition process in a first chamber and the titanium nitride layer may be formed by a thermal chemical vapor deposition process in a second chamber.
FIG. 1 is a plan view illustrating a conventional apparatus for forming a layer.
Referring FIG. 1, a process for depositing a titanium/titanium nitride layer may be successively performed in a pair of chambers. That is, a first chamber 10 may be used for forming a titanium layer and a second chamber 20 may be used for forming a titanium nitride layer. The first chamber 10 and the second chamber 20 may be equipped as a pair. The second chamber 20 may be on standby during wet or dry cleaning of the first chamber 10. Likewise, the first chamber 10 may be on standby during wet or dry cleaning of the second chamber 20. Therefore, operation rates of the first and second chambers 10 and 20 are linked and may be relatively slow.
Moreover, after the process for forming the titanium layer on a wafer is finished in the first chamber 10, the wafer may be transferred to the second chamber 20. Therefore, the wafer and/or the first and second chambers 10 and 20 may be exposed to contaminants. For example, the wafer may be exposed to contaminants during a transfer of the wafer from the first chamber 10 to the second chamber 20. Furthermore, the process for manufacturing the semiconductor devices may be further delayed due to the transfer of the wafer.